CASH, CASH EQUIVALENTS AND SHORT-TERM INVESTMENTS

Cash equivalents consist of instruments with remaining maturities of three months or less at the date of purchase. We classify all of our cash equivalents and short-term investments as “available-for-sale.” In general, these investments are free of trading restrictions. We carry these investments at fair value, based on quoted market prices or other readily available market information. Unrealized gains and losses, net of taxes, are included in accumulated other comprehensive income, which is reflected as a separate component of stockholders’ equity in our Condensed Consolidated Balance Sheets. Gains and losses are recognized when realized in our Condensed Consolidated Statements of Income. When we have determined that an other-than-temporary decline in fair value has occurred, the amount of the decline that is related to a credit loss is recognized in income. Gains and losses are determined using the specific identification method.

Cash, cash equivalents and short-term investments consisted of the following as of February 28, 2014 (in thousands):



	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Current assets:
Cash	$	289,712	$	—	$	—		$	289,712
Cash equivalents:
Money market mutual funds	388,448		—		—			388,448
Municipal securities	6,000		—		—			6,000
Time deposits	32,757		—		—			32,757
U.S. Treasury securities	16,997		2		—			16,999
Total cash equivalents	444,202		2		—			444,204
Total cash and cash equivalents	733,914		2		—			733,916
Short-term fixed income securities:
Corporate bonds and commercial paper	1,343,106		7,847		(382		)	1,350,571
Foreign government securities	11,188		59		—			11,247
Municipal securities	177,752		623		(4		)	178,371
U.S. agency securities	430,012		1,371		(169		)	431,214
U.S. Treasury securities	425,669		759		(111		)	426,317
Subtotal	2,387,727		10,659		(666		)	2,397,720
Marketable equity securities	178		278		—			456
Total short-term investments	2,387,905		10,937		(666		)	2,398,176
Total cash, cash equivalents and short-term investments	$	3,121,819	$	10,939	$	(666	)	$	3,132,092

Cash, cash equivalents and short-term investments consisted of the following as of November 29, 2013 (in thousands):



	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Current assets:
Cash	$	286,221	$	—	$	—		$	286,221
Cash equivalents:
Money market mutual funds	429,373		—		—			429,373
Time deposits	104,711		—		—			104,711
U.S. Treasury securities	14,251		—		—			14,251
Total cash equivalents	548,335		—		—			548,335
Total cash and cash equivalents	834,556		—		—			834,556
Short-term fixed income securities:
Corporate bonds and commercial paper	1,261,375		7,116		(631		)	1,267,860
Foreign government securities	11,213		56		—			11,269
Municipal securities	186,320		328		(24		)	186,624
U.S. agency securities	446,615		1,516		(186		)	447,945
U.S. Treasury securities	424,076		799		(97		)	424,778
Subtotal	2,329,599		9,815		(938		)	2,338,476
Marketable equity securities	177		543		—			720
Total short-term investments	2,329,776		10,358		(938		)	2,339,196
Total cash, cash equivalents and short-term investments	$	3,164,332	$	10,358	$	(938	)	$	3,173,752

See Note 4 for further information regarding the fair value of our financial instruments.

The following table summarizes the fair value and gross unrealized losses related to available-for-sale securities, aggregated by investment category, that have been in an unrealized loss position for less than twelve months, as of February 28, 2014 and November 29, 2013 (in thousands):



	2014					2013
	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
Corporate bonds and commercial paper	$	194,460	$	(382	)	$	225,759	$	(631	)
Municipal securities	6,082		(4		)	13,522		(24		)
U.S. Treasury and agency securities	94,326		(280		)	105,278		(283		)
Total	$	294,868	$	(666	)	$	344,559	$	(938	)

There were 155 securities and 177 securities in an unrealized loss position for less than twelve months at February 28, 2014 and at November 29, 2013, respectively.

As of February 28, 2014, there was one security with a fair value of $0.6 million in an unrealized loss position for more than twelve months. The gross unrealized loss for this security was immaterial. As of November 29, 2013, there were no securities in an unrealized loss position for more than twelve months.

The following table summarizes the cost and estimated fair value of short-term fixed income securities classified as short-term investments based on stated effective maturities as of February 28, 2014 (in thousands):



	Amortized Cost		Estimated Fair Value
Due within one year	$	595,088	$	596,510
Due between one and two years	881,962		885,816
Due between two and three years	697,464		701,525
Due after three years	213,213		213,869
Total	$	2,387,727	$	2,397,720

We review our debt and marketable equity securities classified as short-term investments on a regular basis to evaluate whether or not any security has experienced an other-than-temporary decline in fair value. We consider factors such as the length of time and extent to which the market value has been less than the cost, the financial condition and near-term prospects of the issuer and our intent to sell, or whether it is more likely than not we will be required to sell the investment before recovery of the investment’s amortized cost basis. If we believe that an other-than-temporary decline exists in one of these securities, we write down these investments to fair value. For debt securities, the portion of the write-down related to credit loss would be recorded to interest and other income, net in our Condensed Consolidated Statements of Income. Any portion not related to credit loss would be recorded to accumulated other comprehensive income, which is reflected as a separate component of stockholders’ equity in our Condensed Consolidated Balance Sheets. For equity securities, the write-down would be recorded to investment gains (losses), net in our Condensed Consolidated Statements of Income. During the three months ended February 28, 2014, we did not consider any of our investments to be other-than-temporarily impaired.